[Anemia in students at public schools in Recife: a study of temporal trends].

The scope of this study was to evaluate trends in the temporal evolution of anemia in students ranging from the ages of 7 to 11 in Várzea district (Recife-PE) based on three reports concluded in 1982, 2001 and 2005. An evaluation was achieved in ten public schools in the first study and nine in the last two (one was shut down), in a sample of 305 students (1982), 684 students (2001) and 756 students (2005). Hemoglobin was determined in blood samples taken by venopunction, having two criteria to describe anemia: cut points < 12 g/dL and < 11.5 g/dL. By the first criteria, the prevalence of anemia increased from 8.8% in 1982 to 18.9% in 2001, decreasing to 13.4% in 2005. In the last evaluation, the problem of anemia practically disappeared starting from the age of 9. The evolution of anemia revealed two very different trends: marked elevation in the first phase (1982 to 2001) and a rapid decrease in the second stage (2001 to 2005).